Run results for: weakmap vs closure vs private symbols

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:128.0) Gecko/20100101 Firefox/128.0

Browser: Firefox 128

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

Benchmark engine: Benchmark.js

closure get

1229.1M/s

symbol incr

488.3M/s

closure incr

481.5M/s

weakmap get

33.9M/s

weakmap incr

15.0M/s

View exact numbers

Test name	Executions per second
✓ closure get	1,229,100,032 Ops/sec
symbol incr	488,270,848 Ops/sec
closure incr	481,460,768 Ops/sec
weakmap get	33,947,268 Ops/sec
weakmap incr	14,999,904 Ops/sec

Script Preparation code:

function A() {
	var x = 0;
	return {
		incr() { x ++ },
		get() { return x },
	}
}
var closure = A();
closure.incr()

var wm = new WeakMap();
function B() {
	var x = {
		incr() { wm.set(x, (wm.get(x) || 0) + 1) },
		get() { return wm.get(x) },
	}
	return x
}
var weakmap = B();
weakmap.incr()


function C() {
	var me = Symbol('me');
	var x = {
		incr() { x[me]++ },
		get() { return x[me] },
		[me]: 0,
	}
	return x
}
var symbols = C();
symbols.incr()

Tests:

closure get
closure.get()
weakmap get
weakmap.get()
closure incr
closure.incr()
weakmap incr
weakmap.incr()
symbol incr
symbols.incr()